Cu^(2+)对一种绿球藻生长及生理特性的影响

EFFECT OF Cu^(2+) ON GROWTH AND PHYSIOLOGICAL CHARACTERISTICS OF CHLOROCOCCUM SP.

研究了不同浓度的Cu2+(0.01,0.1,1,10,50,100,200mg/L)对绿球藻(Chlorococcumsp.)生长、形态结构及生理特性的影响.结果表明,Cu2+对绿球藻的显微结构、生长及生理状态的影响比较显著.与对照BG11培养的绿球藻比较,0.01～1mg/LCu2+浓度下培养的绿球藻,细胞壁无明显增厚,色素没有多大变化,但蛋白核由一个变为多个;而在高浓度(10～200mg/LCu2+)下,细胞壁明显增厚为多层,色素减少,蛋白核减少并回复到1个或消失.低浓度Cu2+(0.01,0.1mg/L)对绿球藻生长无影响;高于0.1mg/L浓度时,绿球藻生长变得缓慢甚至出现负生长.在1mg/LCu2+浓度下,绿球藻对Cu2+的去除率最高为90.5%;叶绿素含量及光合作用强度随Cu2+浓度的升高逐渐降低;呼吸强度在0.01～10mg/LCu2+浓度范围内逐渐升高,大于10mg/LCu2+则逐渐降低.结果提示,绿球藻是一种耐受Cu2+胁迫的藻类,对其去除率也高,可以应用于含铜污水的处理.

The effects of different concentrations of Cu^2＋ （0.01, 0.1, 1, 10, 50, 100, 200 mg/L） in BGll on the growth, morphostructure and physiological characteristics of Chlorococcum sp. were studied, and the effects were-obvious. Compared with the cell cultured in BGll, the cell wall of the cells cultured at low concentration of Cu^2＋ （0.01 - 1 mg/L） did not markedly become thick and the chlorophyll did not change notably, but the number of pyrenoid increased. However, the cell wall cultured at high concentration of Cu2＋ （ 10 ~ 200 rag/L） was clearly thickened and became multiple layers, and the pigment decreased and the pyrenoid became one or disappeared. Low concentration of Cu^2＋ （0.01 mg/L, 0.1 rag/L） did not affect the growth of Chlorococcum sp. , but the growth became slow and even negative beyond the concentration of 0.1 mg/L. The removal rate of Cu^2＋ by Chlorococcum sp. was the largest at the concentration of 1 mg/L and reached 90.5%. The chlorophyll contents and photosynthesis decreased gradually with the increasing of Cu^2＋ concentration. The respiration rose gradually in the range of 0.01 - 10 mg/L Cu^2＋ and fell gently over 10 mg/L. These results indicated that Chlorococcum sp. could be applied to treat the wastewater containing Cu^2＋ , because it could endure the stress of Cu^2＋ with high removal rate of Cu^2＋. Fig 3, Tab 3, Ref 17